[MIAaron]

Pics would be best, but at least describe your amp rack and how you have the amps mounted. The kind of fans you find in computers are quiet, but weak. How critical are you of the noise generated by the fans?

 

[MIAaron]

Holy **** that is a lot for a fan.

When dealing with tight spaces you need a fan that can provide pressure. Go with a centrifugal, or squirrel cage, blower like this:
http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=259-132

Try to enclose the amps to ensure good air flow over them.

 

[MIAaron]

What type of fan?